Computing and Telecoms Innovation Award winner 2010

John Cioffi is one of the creators of asymmetric digital subscriber line (ADSL, often referred to simply as DSL) technology, used by telephone companies to provide high capacity bandwidth on standard copper telephone lines that enables broadband Internet access as well as television, video and file sharing applications and voice-over-Internet Protocol on these lines.

Cioffi was a 22-year-old engineer at Bell Laboratories in 1979 when he first calculated that high-speed transmission was capable of speeds up to 1.5 megabits per second on copper telephone lines. He was virtually laughed out of the room at the time by senior engineers who said at most 144 kilobits per second was possible. It took more than a decade for Cioffi to prove them wrong.

Later, as a professor of electrical engineering at Stanford University he developed a technology called Discrete Multitone (DMT), a method of separating a DSL signal into 256 frequency bands or channels. He left the university in 1991 to found Amati Communications to build DMT equipment. His work led to DMT being selected as the US standard for ADSL in 1993. He sold the company to Texas Instruments in 1998 for US$395 million.

DSL accounted for 65% of the broadband market in the first quarter of 2009 compared to 21% for cable, 12% for fibre and 1% for wireless, according to the Broadband Forum.  DSL still maintains the largest market share according to a March, 2010 report by ABI Research. Service revenue for DSL broadband totaled nearly US$100 billion in 2009.

While cable companies are investing huge amounts of money to bring their high speed lines to consumers’ doors, Cioffi hopes to keep DSL around for a long time to come by increasing its speed and reliability. To that end, he founded a new company named ASSIA in 2003.

ASSIA has become the leading provider of high-performance software and services for an emerging growth market known as Dynamic Spectrum Management (DSM), which boosts DSL performance by improving its signal-to-noise ratio. By reducing power DSL consumption, the second generation of DSM yields an average 40% performance improvement. ASSIA is working on a third generation DSM technology, which Cioffi  has predicted could pave the way for 100+ megabit per second data services over existing copper phone lines.

Currently, Cioffi is Chairman and CEO of ASSIA. He remains a Professor Emeritus at Stanford University. He is a member of the US National Academy of Engineering, an International Fellow of the UK Royal Society of Engineering and a winner of the IEEE Alexander Graham Bell Medal in 2010.